Neither a Glock nor an XD nor any other modern well-made firearm will fire unless you pull the trigger. If you are afraid of accidentally pulling the trigger, you need some training and/or practice to help you gain confidence in your own abilities to handle the pistol.

There are several brands of pistols that can be had with thumb safeties, if that is what you decide you want. I am particularly fond of the Beretta lineup, because I think they provide very high quality with a moderate price, but others will chime in with their favorites as well. Beretta makes the 92 and its variants if you want a pistol for home defense and the range. For carry the PX4 lineup, especially the compact version, deserves a look. Both have thumb safeties and a DA/SA trigger in their most common configurations. The latter has a rotating barrel design that tames recoil significantly.

I am one of thousands have carried a Glock for several years without incident. My Beretta 92FS is a much more elegant and refined pistol, beautiful in both aesthetics and function, but both are well-made, reliable pistols, and I trust them both.